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The unprecedented human infection with a former animal flu virus has touched a raw nerve among the public and posed a challenge to China’s disease control system， which is quickly responding to a possible outbreak by drawing upon experiences from previous epidemics.
As an influenza A virus， H7N9 normally circulates among birds. However， the Chinese National Health and Family Planning Commission （NHFPC） confirmed the world’s first three human cases on March 30， including an 87-year-old male and a 27-year-old male in Shanghai who both died from pneumonia symptoms in early March. A 35-year-old female in Anhui Province died on April 9.
According to the daily update of the NHFPC on April 10， the country has reported a total of 33 cases， including nine fatalities. On the same day， a four-year-old boy in Shanghai became the first H7N9 patient discharged from hospital.
A total of 15 cases， including five deaths， have been reported in Shanghai. Jiangsu Province and Anhui reported 10 cases with one death and two cases with one death， respectively. Six cases have been reported in Zhejiang Province， with two deaths.
The commission said that no epidemiological link between those cases had yet been identified and those who have had close contact with people infected by H7N9 have been placed under medical observation， but hadn’t shown signs of infection.
The commission also said that the country’s confirmed H7N9 cases remain isolated and there are no signs of human-to-human transmission.
All identified H7N9 patients show initial symptoms of fever and coughing， which develop into severe pneumonia in later stages.
Measures taken
The Chinese Center for Disease Control and Prevention （CDC） said on April 10 that testing reagents for the H7N9 avian influenza virus have been distributed to all flu monitoring sites across the country and it also provided major infectious disease hospitals and research agencies with testing materials and detection methods.
The CDC said earlier that it is maintaining communication with health authorities in the United States and other countries and regions on relevant technological cooperation. It is also assessing the pandemic risks of H7N9 and working out coping strategies with relevant international experts.
The National Center for Food Safety Risk Assessment on April 7 urged preventive measures to ensure food safety， warning the public to avoid contact with potentially contaminated poultry. The center also cautioned people to thoroughly cook eggs and poultry products， as it believes the virus cannot withstand high temperatures.
A laboratory under the Chinese Academy of Sciences （CAS） announced on April 10 that its researchers have ascribed the human infection to genetic reassortment of influenza strains caused by mingling of different bird populations during migration.
According to the researchers， the genetic reassortment is likely to have occurred in east China’s Yangtze River Delta areas covering Shanghai， Zhejiang and Jiangsu， where a virus carried by migrating wild birds from the Republic of Korea and other regions in East Asia mingled with the avian influenza virus carried by local ducks and chickens.
Researchers also found that no H7N9 genes were traceable to pigs， thus excluding pigs as intermediate hosts for the deadly new strain of bird flu.
Both governments of Shanghai and Nanjing， capital city of Jiangsu， have suspended live poultry trade， shut down poultry markets temporarily and banned entry of live poultry from other parts of the country.
On April 4， the Shanghai Government ordered the culling of all birds in a live poultry trading zone of an agricultural products market after detecting the H7N9 bird flu virus in pigeon samples.
China’s chief veterinarian Yu Kangzhen said on April 7 that infected poultry may show no symptoms at all of H7N9.
Yu told Xinhua News Agency on April 8 that H7N9 bird flu has not triggered an epidemic among poultry in China. Of the 738 samples collected from three live poultry markets in Shanghai on April 4 and 5， where the first known human deaths of the disease were reported， only 20 samples contained the H7N9 virus.
It was the first time the Ministry of Agriculture had detected the virus in animals in China.
Yu said that the possibility of infection among animals in other regions has not been ruled out and the Ministry of Agriculture has called for epidemic monitoring for animals across the nation and special attention to live poultry markets and poultry farms in affected areas. He pledged that the infected animals will be culled and their living environments will be disinfected in order to cut off the spread of the virus.
No need to panic
“Although we do not know the source of infection， at this time there is no evidence of sustained human-to-human transmission，” the World Health Organization （WHO） representative in China Dr. Michael O’Leary said at a news conference held by the NHFPC on April 8. In some of the H7N9 cases， the infected people were found to have had contact with animals， he said， citing the appearance of the virus in pigeons in a Shanghai marketplace.
Though he admitted these cases indicate that the virus may have crossed from animals to humans， O’Leary said that the WHO does not deem it necessary at present to introduce screening measures at ports of entry or adopt any restrictive measures on tourism and trade.
He said that the public should maintain good hygiene and only eat properly cooked meat.
China has started research for the development of vaccines for the H7N9 bird flu virus， said Liang Wannian， Director of the H7N9 Influenza Prevention and Control Office under the NHFPC， at the press conference on April 8.
However， complications in the development and manufacturing process mean it may take about six to eight months before the vaccines can be distributed.
Liang said the decision to put the vaccines into production will depend on whether the virus can mutate to become human-to-human transmissible.
In its first edition of the H7N9 diagnosis and treatment guidance released on April 3， the NHFPC recommended the use of antiviral drugs， including neuraminidase inhibitors as well as some traditional Chinese medicine， on patients.
The CAS announced on April 9 that it has started researching how humans can avoid contracting the H7N9 virus. The project with joint efforts from nine CAS institutes focuses on H7N9’s origin， mutations， pathogenesis and interactions with hosts， among other aspects.
These institutes will conduct scientific evaluations on immune system responses to the virus as well as the performances of antiviral drugs in the hope of accelerating the development of new medicines against the virus.
More transparency
Liang said that China is more prepared in handling public health emergencies than a decade ago when it fought severe acute respiratory syndrome （SARS） as the country’s disease control network and related legislation have greatly improved. During the early stage of the SARS outbreak in 2003， which left more than 5，000 people in China infected， disease control efforts were greatly dampened by the lack of timely quarantine measures and cover-ups of some medical institutions and local governments.
Liang said that governments at all levels have been urged to be more transparent in releasing information on H7N9 bird flu cases. He added that China reported the first case of H7N9 to the WHO soon after the case was confirmed and the country will accept site inspections， communicate with foreign experts， and provide strains of H7N9 avian influenza to the WHO in accordance with International Health Regulations.
At the same press conference， O’Leary said that the WHO had been in cooperation and communication with Chinese officials over the last two weeks.
“We are very satisfied and pleased with the level of information shared and we believe we have been kept fully updated on the situation，”O’Leary said.
Information about H7N9 was made public by the NHFPC the day after the first infection was confirmed.
Since then， the commission has continued to update information on new infections on its official website， detailing the patients’ age， location and treatment. It has also given the public tips on prevention.
“China has learned a lesson from the past in dealing with public health emergencies，” said Professor Wang Yukai at the Chinese Academy of Governance.
“The government’s response to the disease is completely different from 10 years ago， when information disclosure systems had not yet been established，” Wang said.
Over the past decade， the Chinese Government has formulated a series of plans for handling infectious diseases and food safety incidents. A regulation for dealing with public health emergencies came out in May 2003， when the country was at a critical stage in combating SARS. China’s Emergency Response Law went into force in November 2007. A regulation concerning government information disclosure took effect in May 2008， requiring the government to be more transparent in releasing information.
“The Chinese [National Health and Family Planning Commission] is working extremely openly and closely with us on this issue，” said WHO spokesman Gregory Hartl at a news briefing in Geneva on April 9. “We are getting all the information that we need or ask for.”
As an influenza A virus， H7N9 normally circulates among birds. However， the Chinese National Health and Family Planning Commission （NHFPC） confirmed the world’s first three human cases on March 30， including an 87-year-old male and a 27-year-old male in Shanghai who both died from pneumonia symptoms in early March. A 35-year-old female in Anhui Province died on April 9.
According to the daily update of the NHFPC on April 10， the country has reported a total of 33 cases， including nine fatalities. On the same day， a four-year-old boy in Shanghai became the first H7N9 patient discharged from hospital.
A total of 15 cases， including five deaths， have been reported in Shanghai. Jiangsu Province and Anhui reported 10 cases with one death and two cases with one death， respectively. Six cases have been reported in Zhejiang Province， with two deaths.
The commission said that no epidemiological link between those cases had yet been identified and those who have had close contact with people infected by H7N9 have been placed under medical observation， but hadn’t shown signs of infection.
The commission also said that the country’s confirmed H7N9 cases remain isolated and there are no signs of human-to-human transmission.
All identified H7N9 patients show initial symptoms of fever and coughing， which develop into severe pneumonia in later stages.
Measures taken
The Chinese Center for Disease Control and Prevention （CDC） said on April 10 that testing reagents for the H7N9 avian influenza virus have been distributed to all flu monitoring sites across the country and it also provided major infectious disease hospitals and research agencies with testing materials and detection methods.
The CDC said earlier that it is maintaining communication with health authorities in the United States and other countries and regions on relevant technological cooperation. It is also assessing the pandemic risks of H7N9 and working out coping strategies with relevant international experts.
The National Center for Food Safety Risk Assessment on April 7 urged preventive measures to ensure food safety， warning the public to avoid contact with potentially contaminated poultry. The center also cautioned people to thoroughly cook eggs and poultry products， as it believes the virus cannot withstand high temperatures.
A laboratory under the Chinese Academy of Sciences （CAS） announced on April 10 that its researchers have ascribed the human infection to genetic reassortment of influenza strains caused by mingling of different bird populations during migration.
According to the researchers， the genetic reassortment is likely to have occurred in east China’s Yangtze River Delta areas covering Shanghai， Zhejiang and Jiangsu， where a virus carried by migrating wild birds from the Republic of Korea and other regions in East Asia mingled with the avian influenza virus carried by local ducks and chickens.
Researchers also found that no H7N9 genes were traceable to pigs， thus excluding pigs as intermediate hosts for the deadly new strain of bird flu.
Both governments of Shanghai and Nanjing， capital city of Jiangsu， have suspended live poultry trade， shut down poultry markets temporarily and banned entry of live poultry from other parts of the country.
On April 4， the Shanghai Government ordered the culling of all birds in a live poultry trading zone of an agricultural products market after detecting the H7N9 bird flu virus in pigeon samples.
China’s chief veterinarian Yu Kangzhen said on April 7 that infected poultry may show no symptoms at all of H7N9.
Yu told Xinhua News Agency on April 8 that H7N9 bird flu has not triggered an epidemic among poultry in China. Of the 738 samples collected from three live poultry markets in Shanghai on April 4 and 5， where the first known human deaths of the disease were reported， only 20 samples contained the H7N9 virus.
It was the first time the Ministry of Agriculture had detected the virus in animals in China.
Yu said that the possibility of infection among animals in other regions has not been ruled out and the Ministry of Agriculture has called for epidemic monitoring for animals across the nation and special attention to live poultry markets and poultry farms in affected areas. He pledged that the infected animals will be culled and their living environments will be disinfected in order to cut off the spread of the virus.
No need to panic
“Although we do not know the source of infection， at this time there is no evidence of sustained human-to-human transmission，” the World Health Organization （WHO） representative in China Dr. Michael O’Leary said at a news conference held by the NHFPC on April 8. In some of the H7N9 cases， the infected people were found to have had contact with animals， he said， citing the appearance of the virus in pigeons in a Shanghai marketplace.
Though he admitted these cases indicate that the virus may have crossed from animals to humans， O’Leary said that the WHO does not deem it necessary at present to introduce screening measures at ports of entry or adopt any restrictive measures on tourism and trade.
He said that the public should maintain good hygiene and only eat properly cooked meat.
China has started research for the development of vaccines for the H7N9 bird flu virus， said Liang Wannian， Director of the H7N9 Influenza Prevention and Control Office under the NHFPC， at the press conference on April 8.
However， complications in the development and manufacturing process mean it may take about six to eight months before the vaccines can be distributed.
Liang said the decision to put the vaccines into production will depend on whether the virus can mutate to become human-to-human transmissible.
In its first edition of the H7N9 diagnosis and treatment guidance released on April 3， the NHFPC recommended the use of antiviral drugs， including neuraminidase inhibitors as well as some traditional Chinese medicine， on patients.
The CAS announced on April 9 that it has started researching how humans can avoid contracting the H7N9 virus. The project with joint efforts from nine CAS institutes focuses on H7N9’s origin， mutations， pathogenesis and interactions with hosts， among other aspects.
These institutes will conduct scientific evaluations on immune system responses to the virus as well as the performances of antiviral drugs in the hope of accelerating the development of new medicines against the virus.
More transparency
Liang said that China is more prepared in handling public health emergencies than a decade ago when it fought severe acute respiratory syndrome （SARS） as the country’s disease control network and related legislation have greatly improved. During the early stage of the SARS outbreak in 2003， which left more than 5，000 people in China infected， disease control efforts were greatly dampened by the lack of timely quarantine measures and cover-ups of some medical institutions and local governments.
Liang said that governments at all levels have been urged to be more transparent in releasing information on H7N9 bird flu cases. He added that China reported the first case of H7N9 to the WHO soon after the case was confirmed and the country will accept site inspections， communicate with foreign experts， and provide strains of H7N9 avian influenza to the WHO in accordance with International Health Regulations.
At the same press conference， O’Leary said that the WHO had been in cooperation and communication with Chinese officials over the last two weeks.
“We are very satisfied and pleased with the level of information shared and we believe we have been kept fully updated on the situation，”O’Leary said.
Information about H7N9 was made public by the NHFPC the day after the first infection was confirmed.
Since then， the commission has continued to update information on new infections on its official website， detailing the patients’ age， location and treatment. It has also given the public tips on prevention.
“China has learned a lesson from the past in dealing with public health emergencies，” said Professor Wang Yukai at the Chinese Academy of Governance.
“The government’s response to the disease is completely different from 10 years ago， when information disclosure systems had not yet been established，” Wang said.
Over the past decade， the Chinese Government has formulated a series of plans for handling infectious diseases and food safety incidents. A regulation for dealing with public health emergencies came out in May 2003， when the country was at a critical stage in combating SARS. China’s Emergency Response Law went into force in November 2007. A regulation concerning government information disclosure took effect in May 2008， requiring the government to be more transparent in releasing information.
“The Chinese [National Health and Family Planning Commission] is working extremely openly and closely with us on this issue，” said WHO spokesman Gregory Hartl at a news briefing in Geneva on April 9. “We are getting all the information that we need or ask for.”